Penny O'Brian [Cooke] (September 16, 1919 – April 29, 2010) was a Canadian outfielder who played in the All-American Girls Professional Baseball League during the 1945 season.

She started her professional career in Edmonton, and gained notoriety for her blazing speed on the bases as well as in the outfield.

[3] She married in 1944 Earl Cooke, who was serving in the Royal Canadian Navy during World War II conflict.

[5] In just 83 games, the speedy O'Brian stole 43 bases to rank seventh in the league and led all outfielders with 236 putouts.

[3] She is part of the AAGPBL permanent display at the Baseball Hall of Fame and Museum at Cooperstown, New York, unveiled in 1988, which is dedicated to the entire league rather than any individual personality.